Weight distributing shoe shank



Nov. 5, 1957 1 l. E. cox 2,811,791

WEIGHT DISTRIBUTING SHOE SHANK Filed Dec. 24, 1956 2 Shgets-Sheet 1INVENTOR.

IVAN E. cox

Fig. 6 BY WEM A TTORNEY Nov. 5, 1957 1. E. cox 2,811,791

WEIGHT DISTRIBUTING SHOE SHANK Filed Dec. 24, 1956 1 2 Sheets-Sheet 2 5Metatarsal -Cune/form INVENTOR. Fig, 4 IVAN E. cox

BY W/QW.

. ATTORNEY United States Patent 2,811,791 WEIGHT DISTRIBUTING SHOE SHANKIvan E. Cox, Kansas City, Mo. Application December 24, 1956, Serial No.630,291 6 Claims. (Cl. 36'-76) My invention relates to weightdistributing shoe shanks of resilient sheet material, preferablytempered spring steel.

It is a purpose of my invention to provide a shoe shank that is to bebuilt into a shoe by interposition between an outer and an inner sole,that is, of such a character that it controls the bone structure of thefoot so as to distribute the weight of the body on the foot structure inthe way it would be naturally supported, it the normal foot were inengagement with a supporting surface, such as the ground, without beingencased in a shoe. When not hampered by a shoe, as the normal footstarts into forward motion, the weight is first thrown on the heel boneor oscalcis, and after that forwardly on the outer side of the foot,forwardly of the heel or onto the outer longitudinal arch, and finallyon the ball of the foot or metatarsal arch. In the wearing of shoes,because of having heels thereon, normal weight bearing does not existand as a result the outer longitudinal arch of the foot is put under astrain, which produces weakness thereof, and mal-alignment of the archbones, the cuboid, the three cuneiform and scaphoid, and further clausesboth the inner longitudinal arch of the foot to weaken and the foot toroll inwardly or pronate, throwing the inner edge portion of the foot toa lower than normal position. Due to the whole foot structure being inan abnormal position, the two lower leg bones are thrown in a twisted orunnatural position, which causes the legs to appear to be knock-kneed.

The distinct advantage my invention has over other known shoe shanks andsimilar devices, is that it will hold the bone structure of the foot andthe leg bones in a more normal position, and in cases of foot weaknessand mal-alignment of the bones, will help to restore them to normal.

It is a purpose of my improved shoe shank to control and support thebone structure of the foot to produce a normal and natural weightbalancing. Since the heel bone or oscalcis is the largest'bone of thefoot, and the key controlling bone thereof, it is necessary that thisbone be held in its correct position to avoid its twisting, rotating orpronating. This is accomplished, in my new and improved shoe shank, byproviding means for elevating the inner forward portion of the heel ofthe foot, so as to roll the weight to the outer side of the foot orouter longi tudinal arch.

In order to properly support the foot at the outer longitudinal arch, myimproved arch supporting shank is provided with a longitudinal archsupporting portion that is located along the outer side of the insolebetween the forward end of the heel portion of the shoe and the forwardmetatarsal arch supporting or ball portion of my weight distributingshank.

My improved shank further is provided with a transversely elongatedforward metatarsal arch supporting portion that extends from the forwardend of the longitudinal arch supporting portion under all of the bonesof the metatarsal arch structure, and is provided with a domed portionthat curves upwardly from adjacent the side edges and the forward andrear edges of the metatarsal arch supporting portion to a central highpoint substantially midway between said side edges and front and rearedges thereof.

It is the purpose of my invention to provide the-basic structure forshoes that will control and support the bone structure of the foot toproduce a normal and natural weight hearing. In order to accomplish thispurpose it is necessary to provide the above referred to means forelevating the inner forward portion of the heel, the means to supportthe longitudinal arch and the metatarsal arch supporting meanshereinbefore referred to.

It is a further purpose of my invention to provide a fiat marginalbearing edge portion along the forward marginal edge and the outermarginal edge of said metatarsal arch supporting portion that bearsagainst the outer sole, or outsole, of the shoe, and projects theupwardly domed portion upwardly therefrom so that the same rises from anelevation of about one-sixteenth of an inch at the marginal portions ofsaid domed portion to an elevation of about three-sixteenths of an inchat the center thereof to place the bones of the metatarsal arch inproper position and to distribute the weight properly across saidmetatarsal arch, thereby avoiding the dropping of the second, third andfourth metatarsal arch bones, the dropping of which causes callouses onthe bottom of the foot.

It is a further important advantage of my invention to provide a shankstructure, that is of such a character that, while it controls andsupports the entire bone structure so as to distribute the weight'in themanner that nature intended, does not restrict the muscle functions orthe purpose of said inner longitudinal arch, permitting unrestrictedmotion and elongation of the inner longitudinal arch and allowing it toperform its intended function of acting as a spring or shock absorberfor the body.

It is a further purpose ofmy invention to provide a shank for shoes thathas its rear end portion so constructed that it will allow the centralheel nail of rubber heels to be nailed to the insole and which is solocated that it will allow the heel bone of the foot to pocket into theinsole of the shoe, thereby giving additional control to the heel boneand hence to the rest of the foot. Said rear portion of my improved shoeshank comprises a pair of laterally spaced attaching ears that flatlyengage the insole above the shoe heel, but it inclines upwardlytransversely toward the inner side edge thereof and the forward endthereof to the widest part of said rear portion, to thus provide araised or higher inner portion forwardly of the rear end of said rearportion of said shank, that reaches its point of highest elevationadjacent the forward edge of the heel of the shoe on the inner sidethereof, for throwing the weight at the heel of the foot toward theoutside of the foot and toward the outer longitudinal arch.

Other objects and advantages of my invention will appear as thedescription of the drawings proceeds. I desire to have it understood,however, that I do not intend to limit myself to the particular detailsshown or described except as defined in the claims.

In the drawings:

Fig. 1 is a bottom plan view of a shoe, showing my improved shoe shankmounted in position therein, in dotted outline.

Fig. 2 is a fragmentary enlarged vertical sectional view taken on theline 22 of Fig. 1, the shoe upper being broken away.

Fig. 3 is an enlarged fragmentary vertical sectional view taken on theline 3-3 of Fig. 1.

Fig. 4 is a transverse vertical sectional view taken on the line 4-4 ofFig. l, the upper of the shoe being broken away.

Fig. 5 is a fragmentary vertical sectional view taken on the line 5-5 ofFig. 1, through the insole, outsole and shank member.

Fig. 6 is a view similar 6-6 of Fig. 1.

Fig. 7 is a side elevational view of my improved weight distributingshoe shank detached, and

Fig. 8 is a diagrammatic view showing the bones of the foot in dottedoutline and the outline of the shoe and my improved weight distributingshank member in full lines in relation to the foot bone structure.

Referring in detail to the drawings, my improved shoe shank comprises aforward metatarsal arch supporting portion 10, an intermediatelongitudinal arch supporting portion 11 and a rear heel supportingportion 12. Said rear portion 12 comprises a pair of longitudinallyrearwardly extending attaching ears 13 and 14, the car 13 being longerthan the ear 14, and each of said ears tapering slightly toward the rearcurved end edges 15 and 16 thereof, respectively. The ear 13 is bothlonger and extends rearwardly beyond the rear end edge of the ear 14 andsaid ears are spaced from each other so as to provide an opening orcut-out portion 17 lying between said ears to provide for the nailing ofa rubber heel to the insole between said ears 13 and 14.

Said rear portion 12 gradually widens from its rear end to its junctionwith the longitudinal arch supporting portion 11, having an obliquelyextending inner edge 13 that terminates at a point 19 adjacent theforward edge of the heel of the shoe, at the junction with thelongitudinal arch supporting portion 11. The outer edge 20 of myimproved shank extends substantially parallel to the outer edge of theoutsole and insole, the outsole being indicated by the numeral 21. Saidrear portion 12 inclines upwardly from a point substantially as farforwardly as the inner end 22 of the cut-out portion 17 to the junction19 with the longitudinal arch supporting portion 11, and the portionthereof forwardly of the ears 13 and 14 also inclines transversely fromabout the longitudinal center of said portion 12 to the inner edge 18thereof, the in clined portion being indicated by the numeral 23 inFigs. 2 and 3. Thus the junction 19 of the inner concavely curved edgeportion 24 of the longitudinal arch supporting portion 11 with the outerinclined edge 18 of the rear portion 12 is elevated about one-fourth ofan inch higher than the outer edge portion 20 of said rear portion 12 ofsaid arch supporting member, and the cars 13 and 14 that engage theoutsole 21 and insole 25 flatly.

The longitudinal arch supporting portion 11 of my improved shoe shankhas the inner edge 24 thereof concavely curved from the junction 19 ofthe wider rear portion 12 therewith to the junction of the longitudinalarch supporting portion 11 with the forward portion 10, the concavecurvature of the edge 24 being on a longer radius rearwardly of thenarrowest portion 26 thereof than forwardly of said narrowest portion.The outer longitudinal edge 20 of my shoe shank extends at a slightcurvature from the rear portion 12 outwardly to the junction 27 of thesame with the forward convexly curved edge 28 of the forward metatarsalarch supporting portion 10. The major portion of the longitudinal archsupporting portion 11 of said shoe shank, it will be noted, lies on theouter side of the longitudinal center line of the shoe, or along theouter side of the insole and outsole, the only portion thereof that liesinwardly of said center line being the gradually widening portion thatjoin-s it with the rear portion 12 just forwardly of the heel of theshoe, the heel being indicated generally by the numeral 29. If founddesirable, the longitudinal arch supporting portion may be stiffened byproviding a rib or corrugation 30 therein, running lengthwise thereofadjacent the outer edge 20. It will be noted that the longitudinal archsupporting portion 10 inclines gradually downwardly from the rearportion to the forward portion thereof.

The forward metatarsal arch supporting portion 10 exto Fig. 2, taken onthe line tends transversely the full width of the metatarsal archstructure of the foot, as will be obvious from Fig. 8, underlying all ofthe bones of the metatarsal arch. It is of a generally ellipticalcharacter, elongated transversely of the shank and of the shoe, and hasa convexly curved inner edge portion 31 that joins the forward convexedge portion 28 with a rear convex edge portion 32, which joins theconcavely curved inner edge 24 of the longitudinal arch supportingmember 11 in a smooth curve, the forward end of said inner concave edge24 terminating substantially midway of the length of the longitudinalarch supporting portion 10. Said forward metatarsal arch supportingportion 10 is provided with a marginal flange portion 33 that flatlyengages the outsole 21 so as to locate the various portions of theportion 10 at a desired elevation and to prevent the cutting of the edgeof the arch supporting portion 10 into the sole 21. Said flattenednarrow flange portion 33 extends along the forward edge 28 and the innerside edge 31 of said metatarsal arch supporting portion 10.

Said metatarsal arch supporting portion 10 is of a concavo-convexcharacter, being domed up or curving upwardly from all the edges thereoftoward the center of said portion 10, said domed up portion beingindicated generally by the numeral 34. It will be noted upon referenceto Figs. 4 and 5 that the upwardly domed portion 34 of the metatarsalarch supporting portion 10 gradually curves upwardly from the inner andouter ends thereof to the middle thereof, as shown in Fig. 4, and fromthe forward and rear edges thereof to the middle thereof, as shown inFig. 5. Preferably the domed portion 34 is raised about one-sixteenth ofan inch above the marginal edge flange 33 adjacent the same and aboutthree-sixteenths of an inch at its highest elevation at the centerthereof.

In Fig. 8 the bones of the foot are indicated in dotted outline withrelation to the various parts of my improved shoe shank and the outlineof the shoe sole is also indicated therein. It will be noted that themetatarsal arch supporting portion 10 extends completely under all fivebones of the metatarsal arch to support the same, the inner end portion31 thereof underlying the first metatarsal bone of said arch and theouter end portion thereof underlying the fifth metatarsal bone. Thegradually raised dome-like portion 34 underlies the second, third andfourth metatarsal bones so as to raise these in a gradual transversecurve so that these have their natural position with respect to thefirst and fifth metatarsal bones. It will also be noted that the heelportion or rear portion 12 of my improved weight distributing shank doesnot underlie but a small portion of the main heel bone or oscalcis, thuspermitting it to pocket in the heel of the shoe in a desired manner. Inorder to accomplish this, the attaching car 14 is made somewhat shorterthan the attaching ear 13 and the opening 17 is provided instead ofhaving a rear end portion on said shank extending from the edge 18 tothe edge 20 of the shank. It will also be noted that the upwardlyinclined portion 23 of said rear heel portion 12 of my improved shoeshank will throw the weight of the body acting on the foot outwardlytoward the outer edge 20 of the shoe shank and onto the longitudinalarch supporting portion 11 as the weight shifts forwardly in the walkingmotion, and that the entire inner longitudinal arch structure of thefoot is free to move so as to provide the desired cushioning or springaction of said inner longitudinal arch, the concavely curved edgeportion 24 being so located that, from slightly forwardly of the rearheel portion 12 to the metatarsal arch supporting portion 10 there is nometallic shank structure underlying the inner side of the longitudinalarch structure of the foot, the longitudinal arch supporting structure11 only underlying the outer longitudinal arch bone structure, whicharch structure is designed to bear the weight thereon that is graduallyshifted forwardly from the heel portion to the ball portion of the footduring forward movement of the body in a normal walking action.

By providing the upwardly inclined portion 23 to raise the rear heelportion of my improved shoe shank to its maximum height adjacent theforward inner portion of the shoe heel, the weight is thrown toward theouter side of the heel of the shoe and the outer side of thelongitudinal arch portion of the foot, and as pointed out above,progressively toward the forward end of said longitudinal archsupporting portion and to the metatarsal arch as a forward walkingmotion takes place, the raised portion of the rear part 12 of myimproved shoe shank, the longitudinal arch supporting portion thereof,and the metatarsal arch supporting portion thereof operatingsuccessfully to properly distribute the weight and support the weightthat is acting on the foot structure as the forward walking motion takesplace.

If desired a wedge shaped filler member can be placed on the insole andsecured thereto before placing the shank in position, the filler memberbeing located under the upwardly inclined portion 23 of the shank.

What I claim is:

l. A shoe shank of resilient sheet material adapted to be interposedbetween an outer and inner sole, comprising a transversely elongatedforward metatarsal arch supporting portion, an intermediate portion ofless width than said forward portion extending rearwardly from saidmetatarsal arch supporting portion along the outer side of said shank,and a rear portion wider than said intermediate portion and extendinginwardly beyond the inner edge of said intermediate portion, said rearportion hav- 1ng its maximum width adjacent its forward end and beingprovided with a pair of rearwardly extending transversely spaced ears,said wider rear portion inclining gradually upwardly transversely towardthe inner edge thereof and longitudinally toward the forward end thereofforwardly of said ears, the forward inner corner of said rear portionbeing elevated above the outer margin of said rear portion and abovesaid intermediate portion.

2. A shoe shank of resilient sheet material adapted to be interposedbetween an outer and inner sole, comprising a transversely elongatedconcave-convex forward metatarsal arch supporting portion curvingupwardly from the peripheral edges to the center thereof and having flatmarginal supporting edge portions, an intermediate portion of less widththan said forward portion extending rearwardly from said metatarsal archsupporting portion at the outer side of said shank, and a rear portionwider than said intermediate portion and extending inwardly beyond theinner edge of said intermediate portion, said rear portion having itsmaximum width adjacent its forward end and being provided withrearwardly extending flat ear portions, said wider rear portiongradually inclining upwardly transversely toward the inner edge thereofand longitudinally toward the forward end thereof forwardly of said earportions and said intermediate portion inclining upwardly rearwardly tothe forward inner corner of said rear portion to elevate the forwardinner corner of said rear portion above the outer margin of said rearportion and above said intermediate portion.

3. A shoe shank of resilient sheet material adapted to be interposedbetween an outer and inner sole, comprising a transversely elongatedforward metatarsal arch supporting portion, an intermediate portion ofless width than said forward portion extending rearwardly from saidmetatarsal arch supporting portion along the outer side of said shank,and a rear portion wider than said intermediate portion and extendinginwardly beyond the inner edge of said intermediate portion, said rearportion 'having its maximum width adjacent its forward end and beingprovided with a pair of rearwardly extending transversely spaced flatears, said wider rear portion gradually inclining upwardlylongitudinally and transversely toward the inner edge thereof forwardlyof said ears to the forward inner corner thereof to elevate said cornerabove all other portions of said wider rear portion, the outer marginaledge of said shank being slightly concavely curved from the forward edgeof said forward portion to the rear end of said rear portion.

4. A shoe shank of resilient sheet material adapted to be interposedbetween an outer and inner sole, comprising a transversely elongatedforward metatarsal arch supporting portion, an intermediate portion ofless width than said forward portion extending rearwardly from saidmetatarsal arch supporting portion along the outer side of said shank,and a rear portion wider than said intermediate portion and extendinginwardly beyond the inner edge of said intermediate portion, said rearportion having its maximum width adjacent its forward end, tapering inwidth rearwardly from its forward end, and being provided withrearwardly extending flat ears, said wider rear portion incliningupwardly and transversely forwardly from said ears toward the inner edgethereof and toward its forward end to provide a portion of maximumelevation above said intermediate portion and said ears at the forwardinner corner of said wider rear portion.

5. A tempered spring steel shoe shank adapted to be interposed betweenan outer and inner sole, comprising a transversely elongatedconcavo-convex forward metatarsal arch supporting portion havingconvexly curved forward and rear marginal edges, curving upwardly fromthe peripheral edges to the center thereof and having a flat forwardmarginal supporting edge portion, an intermediate portion of less widththan said forward portion extending rearwardly from said metatarsal archsupporting portion at the outer side of said shank, and a rear portionwider than said intermediate portion and extending inwardly beyond theinner edge of said intermediate portion, said rear portion beingprovided with a pair of rearwardly extending transversely spaced fiatears, said wider rear portion inclining upwardly forwardly andtransverse- 1y from said ears toward the inner edge thereof and towardits forward end forwardly of said ears to provide a portion of maximumelevation above said ears at the forward inner corner of said wider rearportion, the outer marginal edges of said forward, intermediate and rearportions being substantially longitudinally aligned, said intermediateportion having a concave inner edge extending rearwardly from adjacentthe transverse middle of said forward metatarsal arch supporting portionto the inner forward corner of said wider rear portion.

6. A shoe shank of resilient sheet material adapted to be interposedbetween an outer and inner sole, comprising a transversely elongatedforward metatarsal arch supporting portion, an intermediate portion ofless width than said forward portion extending rearwardly from saidmetatarsal arch supporting portion along the outer side of said shank,and a rear portion wider than said intermediate portion and extendinginwardly beyond the inner edge of said intermediate portion, said widerrear portion being elevated above said intermediate portion and allother portions of said rear portion at the forward end of the inner sideof said rear portion.

References Cited in the file of this patent UNITED STATES PATENTS1,484,785 Hiss Feb. 26, 1924 1,526,876 Selby Feb. 17, 1925 2,204,410Ganzer June 11, 1940 2,510,560 Daniels June 6, 1950 FOREIGN PATENTS137,921 Australia July 12, 1950 411,382 Great Britain June 7, 1934

